Highly internal phase emulsion (polyHIPE) materials are promising macrocellular foams bearing versatile applications ranging from catalysis, optics, filtration, insulator and so forth. In this critical review water-in-oil HIPE, oil-in-water HIPE and Pickering-based HIPE are discussed. Also in each above-mentioned HIPE family, declination between the organic, inorganic or hybrid-organic foams chemical nature is proposed. The polyHIPE audience is thereby strongly interdisciplinary in nature crossing boundaries of physical chemistry, colloids, polymer science, sol-gel chemistry, hybrid materials, biology and beyond (114 references).